Planning a Python Course for Beginners
Gregory Ewing
greg.ewing at canterbury.ac.nz
Thu Aug 10 19:33:21 EDT 2017
Marko Rauhamaa wrote:
> Of course, some algorithms can (and, we have learned, do) prefer some
> bits over others, but that's inside the implementation black box. I
> would think every bit should carry an approximately equal weight.
Ideally that would be true, but you need to consider the performance
cost of making it so. Dict could go to the trouble of thoroughly
scrambling the hash bits before even making the first probe, but
that would slow down *every* dict lookup.
The way things are, it uses a very simple technique for the first
probe that *usually* gives good results, which speeds things up
overall.
--
Greg
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